EGT Jumping around

I am using a GRT EFIS. Yesterday I noticed my EGT on cylinder 2 fluctuating rapidly from 1300 to 1130 and all temps in between. The other 3 cylinders were stable around 1300F. Anyone experienced this? Does anybody have an explanation?

I replaced the EGT probe this afternoon with a new one I had on the shelf. I have not flown the plane yet. I didn't detect anything wrong with the probe I removed. Wiring and connections looked good.

Engine was running smooth with no issues or vibrations when #2 cylinder EGT fluctuation took place (over the entire flight).

Sounds like a connector issue, either to the probe or at the instrument.

EGT fluctuations.

Did you ever find what was causing the issue?

Connection

Had this happen on a previous aircraft. It turned out that one of the previous owners crimp came loose. Installed a new connector and the indications were rock solid...

Thanks Bob

I replaced the thermocouple, issue has not gone away. However, it has changed up a bit. Now the EGT reads 200 degrees less than the other three in cruise flight. As the EGT gets lower with less power the #2 EGT tends to still stay lower than the other three. Example 1300 on cylinders 1, 3 & 4 and I get about 1100 on cylinder #2. As the power is decreased cylinders 1, 3 & 4 are about 900 and cylinder #2 is at 780. I guess I am going to have to tare into the wiring harness and find the bad connection. If that doesn't work I am going to replace the entire EGT harness for cylinder #2. Keep in mind I am a Long EZ Aircraft (Rear Engine) so all my thermocouple leads have 10 foot extensions. Always fun dealing with wiring issues.